I propose a constitutional amendment:
As long as the US is in debt, it cannot give foreign aid.
LET'S GOOoOoooo!!!
That money is owed by the nation and it cannot afford to incur more debt. If the country has a surplus, then it's up for discussion.
Not sure if that's the legal way to do it.
I would adjust to per county,or per city. The cities that vote to give it away can foot the entire bill, the cities that do not will have citizens keep those funds.